78 SOILS AND THEIR USES 



quantities as to liberate plant food too readily. Sandy soils are 

 more likely to suffer under such treatment than clay soils. The 

 liberated plant food may be lost from the sandy soils more readily 

 than from clay soils. If the lime be in a carbonate form the liber- 

 ation of plant food and the rotting of vegetable matter is slower 

 and the growing crop may use the food as fast as it is liberated. 

 There are a few special crops, such as cranberries, watermelons, 

 and others, which prefer acid soils. These do not thrive on soils 

 where much lime is present. 



Four Great Soil Types. There are a number of special soil 

 types which have been studied and mapped by the Bureau of Soils 

 and which are well known in the sections where they occur. 



Four of these occur abundantly in the Central States. 



1. Fargo clay loam is the principal soil in the Red River Valley. 

 Similar soil is found in a few other ancient lake basins, in North 

 and South Dakota and in Minnesota. These are all formed of 

 glacial sediment. The soil is deep, and rich in humus. The color 

 is dark brown and the texture that of a clay loam. Particularly 

 because of the climatic conditions these soils are abundantly used 

 for the growing of spring wheat, barley and oats. Flax was 

 formerly much grown. 



2. Marshall silt loam covers an extensive area from central 

 and western Indiana through northern Missouri, southern Iowa, 

 eastern Kansas and west beyond the center of Nebraska. In this 

 extensive area it is the most common type of soil found. The soil 

 is well supplied with humus, is very deep and varies in color from 

 brown to black. It is a loose, silty loam and is easily tilled. It is 

 the best corn soil of any extended area. It is the best soil for this 

 purpose in the great corn belt. 



3. Carrington loam is the prevailing soil over the northern 

 region between the Missouri and Mississippi Rivers, including 

 the eastern portions of North and South Dakota, outside of the 

 Red River Valley, southern Minnesota, and northern Iowa. This 

 loam is of glacial origin. It is loose, deep and usually dark or 

 black in color. The soil is well suited to the growing of corn where 

 the climate will permit. Spring wheat is the most important crop 

 of the region; others are flax, barley, oats, winter wheat and hay. 



4. Miami clay loam was the natural forest soil of southern 

 Michigan, eastern Indiana, and western Ohio, with limited areas 

 in Iowa arid in Wisconsin. The soil is of glacial origin and is of a 

 heavy clay or silty texture. It varies in color from dark brown to 



